Ophthalmometer and ceratometer.



J. H. SUTCLIFFE.

OPHTHALMOMETER AND CERATOMETER.

APPLICATION mm JUNE 2|, 1913.

1,142,778. Patented Julie 8, 1915.

2 SHEETS-SHEET I.

THE NORRIS PETERS CO.. PHOTGL!THOU wAsHlNGmN, D. c.

J. H. SUTCLIFFE. OPHTHALMOMETER AND CERATOMETER.

APPLICATION FILED JUNE 21,1913- Patented June 8, 1915.

2 SHEETS-SHEET 2.

THE NORRIS PETERS CO., PHDTO-LITHQ, WASHINGTON, D c,

JOHN HAIVIER SUTCLIFFE, OF LONDON, ENGLAND, ASSIG-NOR T0 GEORGE CULVER LTD-.,

' OF LONDON, ENGLAND.

OPHTHALMOMETER AND CERATOMETER.

I Specification of Letters Batent. Patented'J 11119 8 1915.

Application filed June 21, 1913. Serial No. 775,032.

To all 1127mm it may concern Be it known that I, JOHN HAMER SUT- CLIFFE, a subject of the King of Great Britain and Ireland, residing at 199 Piccadilly, London, W., Great Britain, have in vented certain new and useful Improvements in Ophthalmometers and Ceratometers, of which the following is a specification, reference being had therein to the accompanying drawings.

In ophthalmometers orceratometers of the type wherein that portion of the optical system by means of which the doubling or multiplying of the reflection of the mire is effected, consists of glasses that are adjustable relatively to each other for the purpose of bringing the double or multiple images into contact orvcoincidence, this doubling or multiplying portion has heretofore been connected with its operating mechanism, or other members of the system, in such manner that, in order to inspect, clean, repair, remove for optical purposes, or renew the doubling or multiplying portion, it has been necessary to disconnect mechanical connections such as springs or to remove from the instrument and to take apart the entire optical system; such disconnection, removal and separation of parts involving considerable trouble and risk of injury. 7

Now this invention has for its object to obviate these inconveniences, and according thereto in an instrument of the type described, the doubling or multiplying portion of the optical system is so mounted that it can be inserted orwithdrawn by sliding or otherwise without the necessity of disconnecting any mechanical connection, and without interfering with other members of the optical system, while there is moreover provided for moving the doubling or multiplying portion improved mechanism so constructed and arranged as to permit of the easy insertion and withdrawal of this portion into or from the system.

According to one arrangement the doubling or multiplying portion is mounted in one or more slides, adapted to be inserted into or withdrawn from one or more guides formed in or connected with the frame of the instrument and to be actuated by the mechanism for moving the said element or elements relatively to the remainder of the system. This mechanism preferably comprises one or more devices ofthe kind known as a Chinese Windlass.

of different diameters, are preferably arranged concentrically with the axis of the a p I The two coaxial pulleys of the wlndlass or of each Windlass,

ley and has its ends attached to the coaxial pulleys, and the slide is subject to the action of ,a spring device whereby the chain is maintained in tension. Preferably the cord or chain is first passed also around a pairof guide pulleys mounted on the" frame and then around that portion of theperiphery of the movable pulley which lies nearest tothe coaxial pulleys; this arrangement presentmg the advantage that when the slide is nserted or withdrawn, the movable pulley can simply be moved into or out of contact with the chain, which otherwise would have to be sprung'into or out of its groove. An arrangement of this kind may advanta: geously be employed for mounting the'aux iliary divided lenses of an ophthalometer or ceratometer such as described in the prior specification of .United States Letters Patent No. 890580 and relatively moving the portions of each auxiliary lens in order to double the images of the mire; and the invention is hereinafter described and illustrated by way of example, as applied to the mounting of the auxiliary lenses of a ceratometer of this kind and the movement ofthe marginal portions of these lenses relatively to their central portions which in this example remain stationary during the doubling of the mire image.

In the accompanying drawings, Figure 1 is a veiw on a plane transverse to the axis of the telescope, showing in elevation the frames that carry the slides, one'of these slides withits actuating mechanism being visible; Fig. 2 is an elevation of the said slide when removed from its frame; Fig. 3

shown in Fig. 1- are each provided with guides 3 for the carrier 1 of a slide 5 where on the movable portions 6 of the corresponding auxiliary lens, which in this example are its marginal portions, are mounted, the fixed central portion 7 is attached to the carrier 4: and projects through a slot 8 in the slide. The glasses 6 and 7 are held in position so as to be easily removable by screw clips 9. The co-axial differential pulleys 10, 11 of each Windlass areformed as a ring mounted on the telescope 2, While its movable pulley 12 is mounted on the slide 5. The chain 13 of the windlass is attached at its ends to the coaxial pulleys 10, 11, is carried around the movable pulley 12 on the slide and guide pulleys 141 on the frame, and is maintained in tension by springs 15 connecting the slide with its carrier. Each carrier and guide is normally maintained in position in its frame by means of a detent 16 engaging with the end plate 17 of the carrier. By the disengagement of this detent the carrier with its slide can be withdrawn through a knob 18 and again inserted as desired.

Each pair of coaxial pulleys 10, 11 is, in the arrangement illustrated, rotated to move the corresponding slide in its carrier by means of a handwheel 19.

' lhe telescope 2 has mounted on it the mire 20, suitably illuminated, as by electric lamps 21, and is provided with the usual objective and eyepiece constituting the fixed portion of the optical system, through which the image of the mire formed in the corneal surface is viewed. It will be clear, that by means of the arrangements herein described the auxiliary doubling or multiplying portion 6, 7 of the optical system can be inserted into or withdrawn from the field of view of the telescope and relatively adjusted independently of said fixed portion 22 of the system.

When the carrier 4 is withdrawn from its guides 3, the pulley 12 and the chain 13 are maintained in contact with each other by the action of the springs 15, the coaxial pulleys 10, 11 being rotated to take up the slack of the chain, which thus, when the pulley 12 leaves it, stretches across from one to the other of the guide pulleys 14, ready to engage the pulley 12 on the re-insertion of the slide.

Actuating mechanism such as described can be arranged to impart various kinds of movement to the slide or slides, according to the requirements of the type of instrument to which it is applied; the two portions of the cord or chain on opposite sides of the movable pulley may for instance be parallel, to impart a .uniform movement to the slide or they may be inclined to each other to im part to it a variable movement. Normally the action of the coaxial pulleys is a dif degree of accuracy, varying with the difference the eircumrerences of the coaxial pulleys. l Vhen, however, the coaxial pulleys have been rotated to an extent siifiicient to bring both portions of the chain to the same side of the pulleys, the arrangement becomes an aggregate one, both portions of the chain being simultaneously wound on or unwound from the pulleys; and by this means, when desired, as for adjustment, a rapid move ment can be imparted to the slide.

The facility with which the doubling or multiplying device can be withdrawn, enables the instrument to be easily converted into a corneal miscoscope wherein the lenses consist of the fixed elements of the optical system. The herein described improvements, by providing for interchangeability of the doubling or multiplying portion of the instrument, besides facilitating inspection and cleansing, further simplify the construction of the instrument, and consequently its cost of production and repair.

I claim 1. ln an ophthalmometer, a mire adapted to produce a corneal image, a telescope comprising an objective, guides connected with said telescope, a carrier adapted to be inserted into or withdrawn'from said guides, and an auxiliary lens system carried by said carrier.

2. In an ophthalmometer, a mire adapted to produce a corneal image, a telescope comprising an objective, guides connected with said telescope, a carrier adapted to be inserted into or withdrawn from said guides, and an auxiliary lens system carried by said carrier, a slide movably mounted in said car rier, said auxiliary system comprising two mutually adjustable lens portions, one of which is mounted on said carrier while the other ismounted on said slide, and means for mutually adjusting said lens portions.

3. In an ophthalmometer, a mire adapted to produce a conical image, a telescope comprising an objective, guides connected with said telescope, a carrier adapted to be inserted into or withdrawn from said guides, an auxiliary lens system carried by said carrier, a slide movablymounted in said carrier, said auxiliary system comprising two mutually adjustable lens portions, one of which is mounted on said carrier while the other is mounted on said slide, and means for mutually adjusting said lens portions comprising a pulley having concentric portions of different diameters, a pulley rotatably mounted on said slide, and a flexible member that is passed around said pulley on said slide, and the ends of which are secured wer to the peripheries of the two concentric portions offirst-mentioned pulley. e

I. In an ophthalmomet'er, a mire-adapted to produce a corneal image, a telescope comprising an objective, guides'connected with said telescope, a carrier adapted to be inserted into or withdrawn from saidguides, an auxiliary lens system carried by said carrier, a slide movably mounted in said carrier, said auxiliary system comprising two mutually adjustable lens portions, one of which is mounted on said carrier while the other is mounted on said slide, and means for mutually adjusting said lens portions comprising a pulley having-concentric portions ofdifferent diameters, a pulley rotatably mounted on said slide, guide pulleys mounted on said guides, a flexible member that is secured at its ends to the peripheries of the two concentric portions offirst-mentioned pulley, and that is passed around said guide pulleys and around said pulley on the slide, and spring connections between saidslide and said carrier.

5. In anophthalmometer, a mire adapted to producea corneal image, a telescope com-I prising an objective, guides connected .with said telescope, a carrier adapted to'be inserted into or withdrawn from said guides, an auxiliary lens system carried by 'said carrier, a slide movably mounted insaid carrier,

said auxiliary system comprising two mu-' tually adjustable lens portions, one of. which is mounted on said carrier while the other is mounted on said slide,vand means'fcr mu tually ad usting said lens portio-ns compris- 7 ing a pulley mounted coaxially on said telescope and having concentric portions of different diameters, a handwheel connected to said pulley to rotate the same, a pulleyrotatably mounted on said slide and a flexible member that is passed around said pulley on said slide, and the ends of which are secured to the peripheries of the two concentric portions of first-mentioned pulley.

6. In an ophthalmometer, a'mire adapted to producea corneal image, a telescope comprising an ob ective, guides connected with said telescope, acarrler adapted to be 1nserted into or withdrawn from said guides,

an auxiliary lens system carried by said carrier, a slide movably mounted in said carrier, said auxiliary system comprising two mutually adjustable lens portions, one

of which is mounted on said carrier while the other is mounted on said slide,.and means for mutually adjusting said lens portions comprising a pulley mounted-'coaxially on said telescope and having concentric portions of difierent diameters, a 'lhandwheel connected to said pulley to rotate the'same,

a pulley rotatably mounted on said slide, a

v flexible; member that is passed around said pulley on said slide,.and the ends of which are secured to the peripheries of the two;

. concentric portions'of first-mentionedpulr nected with said telescopeand arranged at right angles toxeach other transversely to the. axis of said telescope, carriers adapted to be inserted into or withdrawn from each of saidv sets ofguides, anauxiliary lenssystem carried by eachof said carriers, a slide movably mounted 111' each carrier, said auxlliary system each comprising two mutually ,ad.

j ustable lens portions, one or which is mount edon said carrierwhile" the other is mounted onsaid slide, and means for mutually adjusting said lens portions. I

9. In an ophthalmometer, a mire adaptedv to produce'a' corneal image, a" telescope comprisingaan ob ect1ve,two sets of guides con? nectedwith 'sald telescope and arranged at rightangles to each 'other transversely to' the axis. oflsaid telescope, carriers adapted ".to be insertediinto or withdrawnrfrom each a of said sets of guides, an auxiliary lens system carried each of said carriers,.a slide %movably mounted in each carrier,said auxiliary system each comprising two mutually adjustable .ilens portions, one of which is mounted on said carrier while the other is mounted on said's'lide, andmeans for mutu-f ally adjusting said lens portions. comprising a pulley having concentric portionsof different diameters, a pulley rotatably mounted on saidslide, and a flexible member that is passed 'aroundsaidpulley on said slide, and the endsof which are secured to the, pe-

ripheries of the two concentric portions of firstunentioned pulley. I 10; In an ophth lmometer, a-ini're adapted to produce a corneal mage, a telescope comprising an'objective, twosets or guides connected with said'telescope and arranged atright angles to each other transversely to the 12o axisof said telescope, carriers adaptedto be insertedainto or Withdrawn :from' each of 7 said sets of guides, an auxiliary lens-system carried by each of said carriers, said auxiliary systems each comprising two mutually adjustable lensportions one of which is mounted on said carrier while the other is mounte'donsaid slide, and means .forfmutually adjusting the'lens portions of each auxiliarysystem.

. 11. In an ophthalmometer, a mire adapted mounted on said slide, and means for mutually adjusting the lens portions of each auxiliary system each comprising a pulley mounted coaxially on said telescope and having concentric portions ofdiflerent diameters, a hand-wheel connected to said pulley to rotate the same, a pulley rotatably mounted on said slide, and a flexible member that is passed around said pulley on said slide, and the ends of which are secured to the peripheries of the two concentric portions of first-mentioned pulley.

12. In an ophthalmometer, amire adapted to produce a corneal image, a telescope comprising an objective, two sets of guides connected with said telescope and arranged at right angles to each other transversely to he axis of said telescope, carriers adapted to be inserted into or withdrawn from each of said sets of guides, an auxiliary lens system carried by each of said carriers, said auxiliary systems each comprising two mutually adjustable lens portions one of which is mounted on said carrier while the other is mounted on said slide, and means for mutually adjusting the lens portions of each auxiliary system, each comprising a.

pulley mounted coaxially on said telescope and having concentric portions of difierent fi'opies of this patent may be obtained for diameters, a handwheel connected to said pulley to rotate the same, a pulley rotatably mounted on said slide, and a flexible member that is passed around said pulley on said slide, and the ends of which are secured to the peripheries of the two concentric portions of first-mentioned pulley, and spring connections between each of said slides and its carrier.

13. In an ophthalmometer, a mire adapted to produce a corneal image, a telescope comprising an objective, two sets of guides connected with said telescope and arranged at right angles to each other transversely to the axis of said telescope, carriers adapted to be inserted into or withdrawn from each of said sets of guides, an auxiliary lens system carried by each of said carriers, said auxiliary systems comprising two mutually adjustable lens portions one of which is mounted on said carrier while the other is mounted on said slide, and means for mutually adjusting the lens portions of each auxiliary system comprising a pulley mounted coaxially on said telescope and having concentric portions of different diameters, a

handwheel connected to said pulley to rotate the same, a pulley rotatably mounted on said slide and a flexible member that is passed around said pulley on said slide, and the ends of which are secured to the peripheries oithe two concentric portions of firstmentioned pulley.

In witness whereof I have hereunto set my hand in presence of two witnesses.

Witnesses:

P. VAnNALs, T. F. PAUL.

five cents each, by addressing the fiommissioner of Patents,

Washington, I). G. 

